Capacity of anaerobic bacteria enclosed in a simulated root canal to induce inflammation.

In an effort to simulate the infected dental root canal, bacteria were enclosed in polyethylene tubes that were subcutaneously implanted into rats. Four different bacterial combinations, selected from nine oral species, were tested. The contents of 144 inoculated and implanted 'root canals' were analysed after 2 and 4 weeks of implantation. Bacteroides, Streptococcus, Actinomyces and Fusobacterium were inoculated in low numbers but dominated the mixed flora at the end of the experiment. The bacteria-filled tubes induced inflammation of the rat tissue at the implant opening ('foramen'). It is confirmed that mixed bacterial populations survive, show succession and develop within an enclosed environment. Such florae cause significant inflammation at the interface with the host tissues.